Beware of Electrolysis…

[tomlamb]

Well my work to my new truck running took a turn for the worse. I have only had this truck for a couple weeks and went to change the coolant only to discover that my lower radiator hose connection was corroded and basically gone. A call to Griffin (it is a 1-55242-X aluminum) tech told me that it looks like electrolysis problem with the coolant. The ground on the electric fan was to the metal shroud through the radiator and core support so when the fan turned on it passed currant through the coolant and basically ate the bottom connection. I never thought something like this could happen, but after a Google search it looks like it is more common then I realized. Just thought I would post this as an FYI to the group and ask if it sounds correct.

If anyone knows about this sort of thing should I bother thying to fix it or get a new radiator?



BTW, They are sending a new lower pipe so I can try to get it welded up and then re-wire the fan. Overall they were a good company to deal with as they said they are sending the new lower pipe at no charge.

[scotts62]

wow thats crazy, ya id probly move some grounds around and away. Thats good that they are fixing you up with the parts.

[tomlamb]

This is what the fan setup looked like, the red line upper part of the photo was the ground. Griffin said the 6/4 was the date it was made so it was only 4 years old (and the last couple it was in a barn).

[1966-Suburban-V-8]

Pull it and take it to a competent radiator shop. They can check to see if further damage was done. Perhaps you got "lucky" and the lower coupler acted as a sacrificial anode. Should be repairable if that's the case.
Definitely run the electrical grounds back to the battery or engine block. Make sure the engine has a HD ground to the battery as well.

Dan

[tomlamb]

Originally Posted by 1966-Suburban-V-8

Pull it and take it to a competent radiator shop. They can check to see if further damage was done. Perhaps you got "lucky" and the lower coupler acted as a sacrificial anode. Should be repairable if that's the case.
Definitely run the electrical grounds back to the battery or engine block. Make sure the engine has a HD ground to the battery as well.

Dan

Thanks for the tip. The couple radiator shops I took it to could not weld it so one sent me to a motorcycle shop that knows how to weld aluminum (waiting on the material from Griffin). The core is epoxy fastened to the tanks do they couldn't inspect the core but what they could see they all said looked "fine". Looking into the tank from the 3 holes it does not look corroded from what is visible but you cannot see the entire core.

Once it is back up and running they said to check the coolant with a meter to see if there is any voltage, I will definitely follow your advice and run a new ground when I put it all back together!

[PrerunnerRob]

Electrolysis isn't necessaraily being caused by the ground issue. Anytime you pass a fluid through different metals the are coupled together, you will create a slight electrical charge, causing the damage you see over time. Even an aluminum or copper waterneck on a cast iron block will do the same, but there is a radiator cap that has a sacrifical anode that will give itself up to combat this. I believe it is called the "rad cap" and I think summit sells it. You can check for this by using a sensitive digital voltage meter, grounding one side, and dipping the other into the coolant.
When pipes are fit together of differnt materials(in building construction), a dielectric union is used that seperates the two materials with a washer or seperator made of plastic or rubber.
I'll see if I can find the radiator cap I was talking about and post back later.
Good luck!

[ChiefRocka]

I think I will purchase one of those caps for my truck...ASAP

[tomlamb]

Originally Posted by PrerunnerRob

Electrolysis isn't necessaraily being caused by the ground issue. Anytime you pass a fluid through different metals the are coupled together, you will create a slight electrical charge, causing the damage you see over time. Even an aluminum or copper waterneck on a cast iron block will do the same, but there is a radiator cap that has a sacrifical anode that will give itself up to combat this. I believe it is called the "rad cap" and I think summit sells it. You can check for this by using a sensitive digital voltage meter, grounding one side, and dipping the other into the coolant.
When pipes are fit together of differnt materials(in building construction), a dielectric union is used that seperates the two materials with a washer or seperator made of plastic or rubber.
I'll see if I can find the radiator cap I was talking about and post back later.
Good luck!

Is somthing like this what you are talking about? If so, it looks like cheep insurance.

[ChiefRocka]

Originally Posted by tomlamb

Is somthing like this what you are talking about? If so, it looks like cheep insurance.

Yes, that is the one.

[greg64]

Neat the effect electrolysis can have, isn't it. This is why anti-freeze has anti-corrosion additives, and why cooling systems that have aluminum parts shouldn't be run on pure water. I'd forgotten about those rad caps, but they do seem like a good idea.

[Iron-Butt]

good info,